Despite a great deal of rhetoric in the public domain about the importance of values as guiding principles for individuals and society, the literature linking values to health-compromising behaviors such as substance use is scant. This proposal takes a social responsibility approach to the prevention of substance use, arguing that high values of social responsibility, instilled in adolescents by parents, translate into an ethic of social responsibility for lower personal substance use as well as greater responsibility for intervening to discourage friends'ATOD use. Parents are a primary source for adolescent values, and this proposal defines family value socialization as parent-adolescent congruence on high parental value messages of social responsibility (i.e., value congruence). Drawing on developmental theory and extant literature, the current research plan proposes four specific aims: (1) Examine the relationship between adolescents'personal values of social responsibility and their ATOD use/intervention intentions with friends, (2) investigate the association between value congruence and adolescent ATOD use,(3) examine the link between value congruence and adolescent ATOD intervention intentions, (4a) test moderators of the relationship between value congruence and ATOD use/intervention intentions using three key aspects of parental influence: democratic parenting, parents'modeling behavior, and parents'ATOD beliefs and(4b) use structural equation modeling to test whether adolescents'personal values mediate the effect of value congruence on ATOD use/intervention intentions. Aims 1-4 use NIDA-funded Social Responsibility and Prevention Project data, a 3-wave longitudinal study of 800+ adolescents ages 10-20 and their parents, and will utilize multilevel modeling techniques to examine developmental change in relationships and within- family variation using mothers, fathers, and a subsample of siblings. Aim 1 also relies on regression analyses of cross-sectional Monitoring the Future data to thoroughly examine the values-substance use link. The prevalence of substance use in adolescence and addictions later in life is a serious public health issue, and preventing substance abuse is a shared responsibility among family, friends, and the broader community. The overarching goal of the proposal is to examine social responsibility values as a way to reduce adolescents'personal risk substance use and abuse, and to also demonstrate the importance of positive influences of family and friends as ways to collectively solve this health problem. Results of the proposed research plan will inform and improve family and peer intervention efforts, and will be shared with the public using various strategies.